Hey all. Quick question: what's the difference between the dbx 160a, 160x and 160xt compressors? I don't own any of them, but I'd like to and it seems the 160x's are the cheapest, followed by the xt's then the a's (on ebay and at used gear shops). I've looked all over the Internet and even on dbx's website, but I can't find any glaring difference. I think I'm just missing something, that's why I'm asking. Thanks, everyone.